An Improved Powertrain Topology for Fuel Cell-Battery-Ultracapacitor Vehicles

A combined battery-ultracapacitor energy storage system is a promising possibility for use with fuel cell vehicles because it combines the advantages of batteries and ultracapacitors. This paper reviews some popular topologies for fuel cell-battery-ultracapacitor powertrains, and presents a new topology which minimizes many of the disadvantages of the other topologies. Simulation results for the new topology are presented and are compared to results for a common fuel cell-battery-ultracapacitor topology. The new topology is shown to improve the fuel economy and reduce the cost of the vehicle.